Punch which is removable from the punched hole by the force of the holepunching blow



United States PatentfO PUNCH WHICH IS REMOVABLE FROM THE PUNCHED HOLE BY THE FORCE OF THE HOLE- PUNCHING BLOW Charles K. Kelley, Fairbanks, Territory of Alaska Application August 18, 1952, Serial No. 304,950

Claims. (Cl. 7-8.1)

This invention relates to combination tools, and more particularly to combination tools especially adapted for working sheet metal.

It is a principal object of this invention to provide an improved tool which can be operated with great ease, speed and safety under varying working conditions.

It is still a further object of this invention to provide an improved combination tool which an operator utilizes to perforate sheet material and which requires handling with only one hand, leaving the operatorsother hand free, thus greatly increasing the ease and efiiciency of sheet metal work.

It is a further object of this invention to provide a sheet metal punch which will be removed from the sheet metal after punching a hole by the force of the holepunching blow.

It is an additional object of this invention to provide a sheet metal punch threadably engaging a weighted head, whereby the head and punch may be utilized either integrally or as separate tools.

It is a further object of this invention to provide such punch and head which are quickly detachable.

It is another object of this invention to provide a tool adapted for punching holes in sheet metal, driving a nail into such a hole, and having means for removing such nails from said sheet metal.

Various tools have heretofore been proposed for perforating sheet material and for applying nails to the perforations thereby made. However, such tools have generally required the use of both hands of an operator and thereby lowered his efficiency and rendered impossible the handling of nails and a punch at the same time. Furthermore, punches heretofore known have either required the additional use of a hammer or driving means, or, in the alternative, have been cumbersome, heavy devices unable to be utilized or manipulated in restricted areas or corners.

Accordingly, it is a further object of this invention to provide a combination tool in which the sheet metal punch may be utilized integrally with a hammer for perforating such sheet material or may be removed therefrom for use in inaccessible areas.

Additional objects of this invention will become manlfest from a consideration of the description, accompanying drawings and appended claims.

In carrying out this invention in one form a hammer having an elongated handle is provided. More particularly, such a hammer is provided which has a threaded aperture in the head transverse to the hammer handle, said aperture being adapted to receive a correspondingly threaded sheet metal punch. This punch is provided with a reduced portion forming a piercing point and the juncture of this reduced portion and the main punch shaft comprises a collar which will cause the punch to be ejected from the sheet metal by the resilient effect of the sheet metal on the collar.

For a more complete understanding of this invention reference should now be made to the accompanying drawing, wherein:

Figure 1 is a perspective view of one embodiment of this invention;

Fig. 2 is a partial view of the embodiment of Fig. 1 from which the punch element has been removed; and

Fig. 3 illustrates the punch element of this embodiment removed from the head.

' Referring now to the drawing, and more particularly to Fig. 1, a combination tool 10 having a hammer, punch and claw portion in accordance with this invention is shown. The tool comprises an elongated handle 11 having a portion 12 of appropriate diameter and shape to be engaged by an operators hand, and a shaped portion 13 adapted to receive a hammer head. A head 14 is secured thereon having a claw portion 15 for removing nails in the customary manner, and a weighted hammer portion 16 for driving such nails. It is the custom in the sheet metal working trade to mount roofing and siding of sheet material upon timber studdings, whereby a complete metallic enclosure is formed. Therefore, it is necessary to first perforate the sheet material at points at which the timber backings or studdings appear, and then to drive nails into the apertures thus made.

In order to perforate the sheet material a punch member 17 is provided having a-threaded portion engaging the head 14. The punch 17 has a reduced, substantially cylindrical portion 18 having a pointed end 20 which forms a piercing point adapted to perforate the sheet material being operated upon. At the junction 19 between the reduced piercing point and the main shaft of the punch, an abutment is formed which is of sufiicient diameter to prevent entry and lodging of the shaftin the sheet material. Upon piercing the sheet material the reduced portion 18 will be drivenginto the timber backing and the abutment 19 will engage the sheet mate-' rial. When this occurs the resiliency of said sheet material will cause punch 17 to be ejected from the hole which it has just created, and will render the tool free for subsequent use. Thus it can be seen that instead of becoming lodged in the sheet material which has been perforated, the punch is automatically removed therefrom and this greatly facilitates and accelerates the performance of the Work.

Under certain conditions it will be impossible to wield the combined structure taught by this invention, and it is therefore desirable that a small punch be available for use in corners, under caves and the like, where limited space is available. The tool taught by this invention is especially adapted for such use in that the punch portion 17 is removably secured in the head 14. In this particular embodiment the punch 17 has a threaded portion 21 which engages a threaded aperture 22 in the hammer head. The threaded portion 21 is reduced to a diameter less than the main shank portion of the punch, and therefore produces a flange 26 which can be tightened down to firmly engage the hammer head and thus prevent loosening of the punch while in use.

The threaded portion 21 of the punch is also provided with a sharply beveled crown 23. This crown is provided to prevent damage to the threads on the threaded portion 21 when the punch 17 and hammer are being used separately. The shank of the punch 17 is provided with an aperture 24 adapted to receive a lever. Such a lever provides means for tightening the punch 17 firmly into the aperture 22. Any means which will provide appropriate leverage for rotating the punch relative to the hammer head will be satisfactory, and the aperture 24 is merely exemplary of one possible system for securing the punch in place.

The shank portion of the punch 17 is also provided with a plurality of flat areas 25 adjacent to the threaded portion 21, and these flat areas 25 are engageable by a wrench or other tool for tightening the punch in place, if desired. However, this would necessitate the use of an additional tool, whereas utilizing the aperture 24 merely requires the use of a nail as a lever. As the workers involved in sheet metal operations will generally carry an abundant supply of nails, a means of punch removal is always readily available.

By having an integral punch and hammer, the risk of loss of the various tools is greatly reduced and the inconvenience of multiple tools is eliminated. Of course, the size and weight of the hammer and diameter of the punch are determined by a consideration of the work being done, the sheet material being used and the size of the nails employed. The particular combination herein shown is merely illustrative of the principles involved in this invention.

While one particular embodiment of this invention is herein described, it should be clear to one skilled in the art that many modifications and alterations can be made without departing from the spirit and scope of this invention.

Without further elaboration, the foregoing will so fully explain the gist of my invention that others may, by applying current knowledge, readily adapt the same for use under varying conditions of service, without eliminating certain features, which may properly be said to constitute the essential items of novelty involved, which items are intended to be defined and secured to me by the following claims.

I claim:

1. A hand punch comprising a handle and head of substantially the size and shape of a hammer and an elongated punch element extending transversely from the middle portion of the head, the free end of said punch element being pointed and adjoining a substantially cylindrical portion, an outwardly extending flat annular shoulder adjoining said substantially cylindrical portion, the length of said pointed and cylindrical portion being restricted to the end portion of said punch element whereby, by a hammer-like blow, a substantially cylindrical hole may be punched in a sheet of metal or the like and said end portion will be retracted from said sheet due to said shoulder striking said sheet.

2. The hand punch of claim 1 wherein the head has a threaded aperture therein, and said punch element has a correspondingly threaded portion in engagement therewith.

3. The hand punch of claim 2 wherein the threaded portion of the punch element is sharply beveled at its free end whereby said punch element may be removed from said head and utilized independently without damage to the threaded portion of said punch element.

4. The hand punch of claim 2 wherein said punch element has formed portions intermediate said threaded portion and said cylindrical portion for engagement during insertion and removal of said punch element from said threaded aperture.

5. The hand punch of claim 1 wherein the head is in the shape of a claw hammer extending transversely to said handle, and comprising a fiat surfaced mass at one end of said head and a bifurcated claw portion at the other end of said head.

References Cited in the file of this patent UNITED STATES PATENTS 257,301 Dubreuil May 2, 1882 768,126 Huber Aug. 23, 1904 974,021 Blake Oct. 25, 1910 2,423,189 Honhart July 1, 1947 2,446,848 Prester Aug. 10, 1948 2,535,588 Mead Dec. 26, 1950 FOREIGN PATENTS 17,280 Great Britain Aug. 8, 1904 372,994 Germany Apr. 6, 1923 543,553 Great Britain Mar. 3, 1942 

